Machine for making compressed concrete



R. C. STUBBS MACHINE FOR MAKING COMPRESSED'CONCREITE Filed Jn, 27. 1927 2 Sheets-Sheet 1 Aug. 9, 1927. 1,638,657

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- R. C. STUBBS MACHINE FOR MAKING GOMPRESSED CONCRETE Filed Jan. 27. .1927 2 Sheets-Sheet 2 'm\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\WM,

u n u n UAM l/// //////////A////// y Ufff@ ROBERT C STUBBS I Z0 um i 0% 'Y alicante/13 lu/vento@ *Patented 'Aug-. 9, 1927.

UNITED STAAT RQBERT C. j STUBBS,

or DALLAS, TEXAS. P;

MCHINE FOR MAKINQ COMPRESSED CONCRETE.

' My invention relates to improvements for laying or constructing pavements, and more particularly to means for laying compressedconcrete pavement which requires distinctively different design of transmitting unit for accomplishing a distinctively different result.` The improved transmitting unit is adapted for use in compressing plain concrete, mixed and placed and struck to grade, l

which is highly plastic, containing relatively high mortar content extending to the surface. Other objects and advantages will be fully explained in the following description and the invention will be more particularly pointed out in the claims. l

Reference is had to the accompanying drawings which form a part of this application.

Figurel is a perspective view of a vibrating machine to which is applied the improve-ment hereinafter set forth.

Fig. 2 isa broken perspective view of the stringers or holders and the 4compressing plates. Fig. 3 is a vertical cross-section of the devices shown in Fig. 2. Fig. 4 is a longitudinal section of the outof-balance element. f

Fig. 5 is an end elevation of the same,

30 showing the position of the parts for 0btaining the maximum out-of-balance eEect.'

Fig. 6 is the opposite end from that shown in Fig. 52 showing the position of parts for obtainmg'partial out-of-balance effect.

Fig. 7 is an end elevation of the same, showing the position of vparts for obtaining neutral effect -of the out-of-balance element.

Fig. 8 is a detail view of devices for shifting the gear. f

Similar characters o f reference are used to indicate the same parts throughout the` f several views.

. The machine has a'motor provided with' driven fly-wheelsl 1 and 2 and a shaft 3 therefor which is journaled in a frame 4. The motor is provided with a crank-case 5. The machine is provided with out-of-balance elements which are mounted on and n operated by a shaft 6 which is journaled in frame 4. The out-of-balancing elements include an outer cylinder provided with a weighted side 7 and a light side 8. flhe inner cylinder has -a weighted side 9 and '55 a .light side 10. The out-of-balancing elements include a friction wheel 14 which Application mea January 27, 1927.J serial No. 164,094.

is j ournaled in a yoke lever 15 which is carried by a fulcrum 16 which is mounted in the frame 4. The yoke 15 is used to hold the wheel 14 in mesh or against the face of the 'wheel 1 so that the wheel 14 will be driven by the wheel 1. The yoke 15 is provided with a handle 18 for operation of the yoke and for adjusting the wheel 14.

The vibrations are created by the inner ,and outer cylinders and transmitted tok the frame 4 and from the frame 4 the vibra- .tions are transmitted through rollers 21.

The shafts 22 of the rollers 21 are journaled in bearings 23 which are rigid with the frame 4. vThe rollers 21 transmit the vibrations to the transmitting ,-u'nit which c nsists of a device in the nature of a platfo 1n composed of stringers 24 which are so var-v ranged as to permit air` and excess water and mortar to escape from rthe concrete through the surface of the concrete or plastic mass which is being treated with the pressure and vibrations.

j The inner cylinder may be keyed to the shaft 6 as shown in the drawings so 'that it will revolve with the shaft 6. The4 outer cylinder may be held at any required point of adjustment relative to the inner `cylinder by a collar 11,l which is rigid with the inner cylinder and is provided with acorrugated or notched periphery, and by a dog or plunger 12 which is yieldably mounted on -a spoke ofthe cylinder and adapted to engage any one of the corrugations or notches in the collar 11. The dog 12 is carried by a spring 13 which is attached to the spoke of the puter cylinder. lThe cylinder out-of-balance elements may be returned to normal position by the involute spring19. A brake shoe 2 0 is provided for further controlling the speed of the cylinder out-of- `balance element.

The machine, as above described, is adapted for laying or constructing types of paving known as Vibrolithic and Armorplated paving. It requires something di'erent to lay or construct compressed concrete paving. It is necessary to distinguish the two operations by understanding that in the operation of 'compacting or making compressed concrete, excess water and air only are to be expelled from the mass. No mortartis reuired or desired to be brought to the surface, it being cleafr that finishing mortar already exists at the'top ofthe mass, and overwet morta-r is distributed throughout the entire mass, 'and it is necessary that much of such water be driven from the ma'ss and be permitted to'escape at the surface as naturally there is-no other means or avenue of escape for excess water from the concrete slab spread uponthe earth' or prepared grade.

Therefore, theJ problem was to draw out thel water and air without bringing the mortar up, or to squeeze out the water andto compact the mortar in layers between the aggregate of the slab. The improvement shown "in the accompanying drawing includes a metallic sheet or plate 26 which is attached to the stringere 24 of the former transmitting unit. The sheetA 26`has a plurality of ,per-

forations 27. The perforations 27 are rela-f tively small and will permit only air and surplus water to rise up `out kof the concrete mass. The perforationsf27 may be of various sizes and shapes for accomplishing various forms of construction, but for laying paving t-he perforations are preferably as'shown thrown upwardly on the operators.

inthe drawings. The perforat-ions 27 are made by slitting' the plate 26 and then pressing themetal on one side of each slitl upwardly, as Ashown in Figs.2 and 3 to form baiies 28 to cause uprising water to be spread evenly and to prevent the water 'from being The openings 27 are small as compared with the total area' of the plate 26, the ratio of the area of the openings t-othe area of the plate 4 being approximately one to fifty. The object is to make 'the openings 27 so small that mortar` will not pass through the openings butair and surplus water are allowed to paction and forcing out of water and air. y

The mortar will be compacted on the Surfaces of the stone which constitutes the aggregate, but practically no mortar will pass through the'plate 26. The mortar and the aggregate will be solidified into a compressed concrete. l/Vith the compressing plate, such rs is described above, a very high percentage of the surface mortar solids are compacted by the great contact area of the plate rather than being forced out lthrough the apertures 27.

What I claim, is 1. In a device for compressing concrete by means of vibrations; a plate adapted to be placed' in contact with freshly laid plastic and provided with openings for escape of air and surplus water and provided .with means for `controllingthe direction of theescaping ^air and water.

2. In a device for compressing concrete by means of vibrations; a plate adapted to be pla-ced in contact with freshly laid plastic and provided vwith direction controlling openings for escape of air and surplus water and provided withl direction controlling openings for escape of air and water.

3. In a device for compressing concrete by i means of vibrations; a plate adapted .to be placed in contact with freshly laid plastic and provided with openings for escape of air,

and surplus water and means associated with said openings for spreading the water in predetermined directions.

. 4. A device of the character described for making compressed concrete comprising a plate. for applying to a mass of freshly laid concrete. and provided with openings -fr escape of air and surplus water and bailies f associated with said openings for controlling the direction ofthe escaping water.

In testimony whereof, I set my hand, this 24day of January, 1927. a ROBERT C. STUBBS. 

